Virtualization is supposed to simplify administration. Virtualization adds flexibility and efficiency to the IT infrastructure. Its potential to reduce overall footprint in the data center by making better use of server resources benefits the entire IT organization by trimming costs and freeing up money and people to perform revenue-producing work. But to reach these goals, you also need to obtain some new knowledge.

I will have a walk-through in my next post since I`m going to install and configure a
brand new lab-environment, and try to show some pros and cons about
virtualization vs. physical.

Thursday, September 23, 2010

Everybody knows that the ideal machine, is a clean machine where the workload are newly installed and configured.

But sometimes you need to do a conversion of a physical server to a virtual server (P2V).

It`s supposed to be a simple process, but it can result in late nights and a lot of coffee if you skip the planning process.

Conversion tip 1:

Prepare for downtime since the conversion is making a copy of your Physical machine.

Even though you could run an Online conversion, you should not let the source be ‘online’ for connections during the conversion. In practical, you are running an online backup of your physical machine, so if its accessible for your users, the data you convert will be outdated.

Example:

If you convert a machine running SQL server in your network, you might want to stop your SQL server engine during conversion, or simply deny the traffic with the firewall.

Conversion tip 2:

Have you checked your network and storage requirements ?

If you don’t have enough storage for your vm, you will have a problem. Check the disk size on the source before conversion.

The conversion brings a heavy load to your network, even though it`s using BITS. Do not run a conversion during peak performance. Consider performing the conversion on a dedicated network.

Also consider if you can convert your physical machine to a virtual machine with dynamic disks, and convert the disks to Fixed afterwards. This will result in a quicker conversion. (But the conversion from dynamic to fixed can only be performed when the vm is off. Again: prepare for some downtime)

Conversion tip 3:

Select your migration candidates in order of importance. Test the conversion on your non-business-critical workloads before your LOB server. You will get the experience, and clear some ‘gotchas’ before the ‘real’ conversions starts.

Conversion tip 4:

Assign more resources to your vm. The great benefit of virtualization, is that you can assign extra ‘hw’ to your vms more easily.

Want to be able to share your isolated test machines without connecting them to your corporate network ?

It`s possible with SCVMM 2008 R2 and the Self Service Portal.

Let`s assume that everything is installed, and the VMs need to be accessible over the network without being physical (or virtual) attached.

In SCVMM, you create a new user role, so you can assign the VMs to the portal.

1. Navigate to the administration view
2. Click 'User Role'
3. Click 'New User Role' from the actions pane to get to the 'Create User Role Wizard'

After providing a name for your new user role (And selected the Self-Service User profile), click next to add members to this user role.

Add a user or a group from Active Directory.

On the the 'Select Scope' page, check the host groups to which you want this new user role to have access (This is very important. If you`re not checking the host group where the VMs will be placed, they will not appear in the Self-Service portal).

On the Virtual Machine permission page, you can specify what action this new role can take on the VMs in the scope. I would recommend that you uncheck the 'Checkpoint' if you are running the VMs in Failover Clustering, since it will create a differencial disk (.avhd).

The next page shows the Library Share.This is where you allow users to store virtual machines in the library which this user role has access.

The next page is the summary of what you`ve been up to.

After you`ve finished, you have to assign an owner to the VMs that you want to expose in the Self-Service Portal.

Navigate to 'Virtual Machines' in SCVMM, right click the VMs, select 'Properties', and select the same group from Active Directory that you assigned the newly created User Role.

You can now log on to your Self-Service Portal, and see the selected VMs.
The reason why you can log on to your VMs without connecting them to your network, is that your SCVMM connects to the Hyper-V host through VMConnect.exe (default on port 2179).
(Also make sure your VMs have the intergration services installed prior to this)

When you now log on to your Self-Service Portal, you should see the selected VMs.

Tuesday, September 21, 2010

Since you have a High Availability solution available in Hyper-V with Failover Clustering, why should you consider Guest Clusters ?

Some reasons for considering a guest cluster, is when you need a High Available solution for your SQL servers.

Example: When SQL server is installed in a two-node Failover Cluster, the SQL Server service is installed on both nodes of the cluster. When one of the nodes fails, the remaining node will quickly take over the processing that was being done on the dead node.
If you only had a single SQL server VM in a Hyper-V Failover Cluster, the SQL Server would restart on the remaining node in the cluster, having time consuming tasks to be completed before beeing able for client requests.

Requirements for Guest Cluster:
You can only use ISCSI for guest clusters.
To build a guest cluster, you should follow the same steps as you would do for a 'normal' cluster, using ISCSI.

Why should you use Quick Migration if Live Migration provides more uptime ?

Live Migration can place a heavy burden on networking resources to accomplish the VM move.
Since there is a heavy load, only one vm can migrate at a time using Live Migration, and if the load are really heavy, the migration might fail.
Quick Migration saves the mamory state of VMS to be moved, and are capable of moving multiple VMs from one node to another at the same time. The VMs are 'frozen', and might not be acceptable for some organizations, so be sure to select the right migration.